Miniature video cameras have recently been incorporated into a wide variety of diagnostic instruments for producing a video image of a concealed target. Such instruments include, for example, laparoscopes, endoscopes, and borescopes. These prior devices require a separate source of illumination, and a fiber optic conduit to carry the light forward to illuminate the target.
In addition to this known video technology used in association with these relatively large diagnostic instruments, a number of smaller diagnostic instruments exist for the direct examination of tissue so that a medical practitioner can diagnose the health of such tissue by inspection of a particular patient. These types of diagnostic instruments include, for example, otoscopes, epidural scopes, and dental mirrors. Such instruments, however, require the practitioner to place the practitioner's eye near or on the instrument to conduct an inspection of the subject target while an image of the inspected tissue remains solely as a mental impression within the practitioner's memory. It is impossible with these conventional instruments to create any sort of hard copy record or permanent image of the object or target under inspection.
These limitations of the prior art have been overcome by the applicants. The present device incorporates these features and further adds the desired function of remote operation.
Accordingly, it is a principal object of this invention to provide a remote hand-held diagnostic instrument which includes a miniature video imager, focusing optics, and a light source, as well as necessary electronic circuitry to produce a monitor-ready standard video signal, so that an industrial inspector or medical practitioner can view a target on a standard video monitor.
It is another object of the present invention to provide a line of hand-held devices for different industrial and clinical purposes, the devices being generally common in style and function with a specific type of head cover.
A further object of this invention is to provide a hand-held instrument with adjustable focusing optics whose focal length can be changed manually such that a user of the instrument can hold the instrument and adjust its focus with one hand.
Yet another object of this invention is to utilize a single remote video diagnostic instrument in conjunction with a number of different video monitors positioned in different patient examination rooms or areas.
These and other objects are attained in accordance with the present invention wherein there is provided a remote hand-held diagnostic instrument with video imaging capability, and transmitter means for remotely transmitting and receiving a video signal. According to one aspect of this invention, the hand-held diagnostic instrument is provided with a casing or housing that has a hand-holdable body portion, a neck portion that extends forward from one end of the body portion, and a head portion situated on the distal end of the neck portion. The head portion is comprised of a back cover and a front cover. An arrangement of circuit boards is fitted into the body portion of the casing and contains video processing circuitry. A circuit board and/or flexible circuit member extends from the body portion through the neck portion of the casing and provides a receptacle for a head member which is positioned in the head portion of the casing. A solid-state imager, such as a CCD chip, is carried in the head member and is connected with the video processing circuitry on the circuit boards. A focusing lens assembly is carried in the front cover and focuses onto the imager an image of an object in the field of view of the lens assembly. The diagnostic instrument is connected to a remote transmitter capable of being suspended from a practitioner's belt or clothing. The transmitter transmits the video signal to a remotely located video monitor equipped with a receiver. In this manner, the practitioner is free to move without being limited by a hard-wire cable between the device and monitor.
In one preferred embodiment of the present device, the lens assembly includes a dual stage manually actuated mechanism for adjusting the focal length. A miniature lamp is carried on the head member displaced a small distance from the imager. The front cover is provided with a window or opening that directs illumination from the lamp into the field of view of the focusing lens assembly. A conduit or cable carries a processed standard format video signal to the portable transmitter. A battery pack contained in the transmitter, provides forward power to the lamp, imager, and image processing circuitry. The picture on the monitor is an image of the target as viewed by the imager in the instrument. This picture can be digitized and captured, for example, for storage in a magnetic memory of a small computer. A hard or paper copy of the image can then be generated.
The head cover and neck incorporate an air tight seal allowing the device to be disinfected after a clinical use. Disposable transparent sterile sheaths can be employed to cover the head and neck to prevent contamination from a patient's body fluids. In addition, the front and back covers of the head portion can be detachable and interchangeable with covers, optical assemblies, and air tight seals of another style to convert the instrument, for example, from a nasal probe to an otoscope.